Semileptonic decays of B_c involoving vector mesons in self-consistent covariant light-front quark model

We present an extensive and systematic investigation of the semileptonic B_c → V decays within the self-consistent Covariant Light-Front Quark Model (CLFQM), a framework that provides a covariant and internally consistent description of hadronic transition dynamics in heavy–heavy meson systems. Traditional light-front approaches often suffer from ambiguities associated with spurious ω-dependence and zero-mode contributions, which can distort the extraction of physical form factors. The self-consistent CLFQM addresses these challenges by imposing explicit self-consistency conditions on the light-front vertex functions, thereby eliminating spurious contributions and ensuring that the resulting hadronic matrix elements are covariant and free from model artifacts. Within this refined theoretical framework, we compute the complete set of vector and axial-vector form factors for the B_c → V transitions and examine their behavior across the entire kinematic range. To achieve a stable and reliable representation of their q²-dependence, we employ a model-independent z-series expansion. Using these form factors, we present numerical predictions for a variety of physical observables, including branching fractions, forward–backward asymmetry, lepton-polarization fractions, etc. The results highlight the improved internal consistency and predictive capability of the self-consistent CLFQM and offer updated Standard Model benchmarks for B_c semileptonic channels. This study contributes to a deeper understanding of nonperturbative QCD effects in heavy meson systems and supports ongoing experimental and theoretical efforts aimed at probing heavy-quark dynamics and testing lepton-flavor universality.